A conventional, general image shooting/playback apparatus comprises a so-called input-output device which writes data on an external storage medium and reads out data from it so as to store shot images and to play back stored images. Also, the image shooting/playback apparatus comprises a file system used to manage a large number of image data as image data files in the external storage medium. Accesses to check what image data files exist in the external storage medium, and the like are made via the file system. This file system can assign attributes to files so as to manage and limit use of files with respect to access requests from a program (see Japanese Patent Application Laid-Open No. 5-334164). File attributes under the management of such file system will be referred to as file-system file attributes in the present application.
The external storage medium may be connected to another apparatus which comprises an input-output device. When an apparatus such as a PC which comprises an input-output device interprets file management of the file system in the external storage medium and makes accesses, the file-system file attributes are used to manage and limit use of image data files. For example, when the image shooting/playback apparatus alters a file-system file attribute of an image data file stored in the external storage medium from “normal” to “protect”, the file-system file attribute when that image data file is accessed by the PC is also recognized as “protect”. Conversely, when the file-system file attribute of an image data file in the external storage medium is altered from “protect” to “normal”, the file-system file attribute when that image data file is accessed by the PC is also recognized as “normal”.
The file-system file attributes of image data files stored in the external storage medium can be assigned to image data files under the management of the file system independently of apparatuses connected.
Attribute information of a target file is saved in, e.g., anther file, and that file is used according to the saved attribute information.
However, image data files which are shot by the image shooting/playback apparatus and are stored in the external storage medium are interpreted in different ways depending on apparatuses connected. For example, when a program on a personal computer accesses an image data file which is stored in the external storage medium from the image shooting/playback apparatus, the structure of that image data file may be destroyed due to misinterpretation of the image data file.
Hence, after the image shooting/playback apparatus stores an image data file in the external storage medium, it alters the file-system file attribute of that image data file to “protect” so as to prevent the image data file from being destroyed when the external storage medium is connected to another connected apparatus. However, even when the image shooting/playback apparatus which will not destroy the image data file accesses that image data file, the image data file is handled as that with “protect”. Hence, before write access such as deletion, editing, and the like of the image data file, the user must manually cancel “protect”.